Friday afternoon a massive earthquake struck Japan. Magnitude it was, according to various estimates, from 8.9 to 9.1. It should be noted that when compared with last year's energy developments devastating earthquake in Haiti, a magnitude 7.0 (read: "The disaster in the island"), using the formula M = 2/3 (lgE — 11,8), where M — the magnitude and E — the energy of the earthquake in joules, the current will be about a thousand times more powerful (1025 vs. 1022 joules). The earthquake was the strongest in the history of Japan and one of the most powerful of the seismic observations — maybe it will even top five.
Fortunately, this time the epicenter was located in the sea near the coast of Honshu. But not far enough, 140 km from the city of Sendai, with a million people and 370 km from Tokyo. He came in a very active area of the Japan Trench, deep depression for several kilometers under the seabed where the Pacific plate dives beneath the Okhotsk. Knowing the danger of the area, the Japanese are paying great attention to the seismological research and technology, and the result of the event was not nearly as awful as last year in Haiti.
Interestingly, the event happened during kakih-nibud days after the Sun the first time in a long time was recorded very strong activity. On the eve of a sunspot, received number 1164, there was a powerful coronal mass ejection. Substance rushed into space at a speed of 2200 km / s — this was the strongest indicator of the release, the past six years. A significant fraction of the charged particles emitted March 8-9, reached the Earth and caused a geomagnetic storm. Soon rocked Japan.
Currently there is no generally accepted explanation of earthquakes, but some experts believe that its role in this can play and solar activity, which at times allows the bowels of the Earth to dump the stored energy strain, pressure, and temperature. One of these experts, the American meteorologist Kevin Martin (Kevin Martin) suggests that this relationship is obvious. He said: "A lot of past earthquakes also coincided with solar flares … Maybe in Japan would not have happened without the sun occured this ejection of matter."
Is it really impossible to say today, but the earthquake has become truly global. According to the calculations of the JPL geophysicist Richard Gross (Richard Gross), a result of past mass redistribution has shifted the axis of rotation of the Earth — or more precisely, the line around which the planet's mass is balanced. Sdvinuvshis approximately 0.15 m, it has led to the fact that the speed of rotation of the Earth has increased, and the length of the day was reduced by 1.6 microseconds. As suggested by Gross, similar effects at all typical of earthquakes that level — the current manifested itself slightly stronger than last year's strong tremor in Chile (1.26 ms — read: "Chilean shock"), but much weaker than the earthquake in Sumatra in 2004 ., when night fell by 6.8 microseconds.
Unfortunately, it's not limited to earthquake. The shaking of the sea has led to the tsunami waves. Waves as high as 10 feet high, covered the coastal areas of Japan. Tsunami spread rapidly throughout the Pacific — its waves can travel at speeds of good aircraft, to 850 km / h, and while approaching the shore slow, but gaining height. Wave rolls reached almost the entire coastline of the ocean, from Kamchatka to New Zealand, from Indonesia to the United States.
These terrible events with new urgency put a question on the possibility of predicting earthquakes. Today, Japan has the most advanced earthquake warning system in the world, representing more than one thousand seismographs located throughout the country. Together they are able to notice even the smallest tremor, automatically process the data and send the warning most "earthquake-prone" services — railways, power plants, industrial plants, giving them some time to slow down the speed of the trains, shut off the gas in pipelines, etc . on Parallel warnings transmitted on television, the Internet and sending SMS to cellphone.
Indeed, in Japan, seismographs recorded the primary P-wave and instantly calculate the location of the epicenter. After a few moments had come more powerful S-waves. The system took about ten seconds for it to assess the risk of an impending earthquake. In normal velocity of the secondary S-waves of about 4 km / s, they would reach Tokyo in about 90 seconds.
Is — alas — the power of the predictions at this stage, 80 seconds was the residents of the Japanese capital out to take some extra steps. That during this time you can do? In fact, not too little. You can stop the elevator and out of it, stop the car and park at the curb, stop procedures and operations at the hospital …
The appearance of the tsunami took more time. The government has issued an official warning of its approach a few minutes after the earthquake hit, and only after a specialized computer system in Japan and the United States previously shortchanged upcoming event. Issue warnings wasting government was not to undermine people's confidence in such performances. So, only by appreciating aftershocks, location of the epicenter, the expected bottom deformation and displacement, and so on, and so on, scientists have confirmed that the tsunami will be, and will be powerful.
Despite all of the destruction wrought by the wave, they would be much more if the system did not work. Residents of the coastal regions of Japan issued a warning 15 minutes before, and Tokyo — more than 40 minutes. And the whole country suffered not so much as one would expect. After the devastating earthquake in Kobe in 1995 were made by the most serious conclusions, which then affected the practice. In Japan, there are very stringent requirements for seismic resistance of buildings and other structures. According to geophysicist Stephen Rondeneya (Stephane Rondenay), «The blow fell on the country, the best anyone in the world ready for earthquakes."